World power consumption

World power consumption is 15 TW. World electricity consumption is
2 TW.

Useful conversion factors

To change TWh per year to GW, divide by 9.

1 kWh/d per person is the same as 2.5 GW per UK, or 22 TWh/y per UK

To change mpg (miles per UK gallon) to km per litre, divide by 3.

At room temperature, 1 kT = 140eV

At room temperature, 1 kT per molecule = 2.5 kJ/mol.

Meter reading

How to convert your gas-meter reading into kilowatt-hours:

Calorific values of fuels

Crude oil: 37 MJ/l; 10.3 kWh/l.
Natural gas: 38 MJ/m3. (Methane has a density of 1.819 kg/m3.)
1 ton of coal: 29.3 GJ; 8000 kWh.
Fusion energy of ordinary water: 1800 kWh per litre.
See also table 26.14, p199, and table D.3, p284.

Heat capacities

The heat capacity of air is 1 kJ/kg/°C, or 29 J/mol/°C. The density of air
is 1.2 kg/m3. So the heat capacity of air per unit volume is 1.2 kJ/m3/°C.

Latent heat of vaporization of water: 2257.92 kJ/kg. Water vapour’s
heat capacity: 1.87 kJ/kg/°C. Water’s heat capacity is 4.2 kJ/l/°C.

Steam’s density is 0.590 kg/m3.


Atmospheric pressure: 1 bar 105 Pa (pascal). Pressure under 1000 m of
water: 100 bar. Pressure under 3000 m of water: 300 bar.

inland water 0.083
rail 0.083
truck 0.75
air 2.8
oil pipeline 0.056
gas pipeline 0.47
int’l water container 0.056
int’l water bulk 0.056
int’l water tanker 0.028
Table I.8. Energy intensity of transport modes in the USA. Source: Weber and Matthews (2008).